Straddle packer wire line tester



Dec. l2, 1967 G. G. CALHOUN STRA'DDLE PACKER WIRE LINE TESTER 5Sheets-Sheet l Filed June 7,

Dec. 12, 1967 G. G. CALHOUN STRADDLE PACKER WIRE LINE TESTER 3Sheets-Sheet 2 Filed June '7, 1965 6. Calhoun I\IVENTOR` Amami wpa/104],

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United States Patent O 3,357,504 STRADDLE PACKER WIRE LINE TESTER GeraldG. Calhoun, 4309 Bedford, Midland, Tex. 79701 Filed June 7, 1965, Ser.No. 461,655 9 Claims. (Cl. 175-4.52)

ABSTRACT F THE DISCLOSURE A wire line well testing tool having anelongated cylindrical body member provided with a straddle packer meansfor selectively positioning the tool to isolate a portion of a wellbore, wherein packers are expanded into gripping engagement with a boreby expanding gas produced by the ignition of a combustible gas or thedetonation of an exposive within a tiring chamber comprising a part ofthe packer setting means and wherein movement of the annular pistonsimultaneously actuates a valve means to permit formation fluid to enterthe body of the tester so as to `permit it to be analyzed by a pluralityof ins-truments therein and/ or recovered thereby.

This invention relates generally to a well testing tool adapted to belowered into and raised from a well bore by means of a cable connectedto suitable hoisting means at the earths surface. More specifically,this invention relates to a wire line tester utilizing a straddle packerto obtain data pertaining to the productivity of a formation penetratedwhile drilling a well. Thus, the expanded packers prevent the drillingfluid in the annulus from entering the section between the packers whichis undergoing testing thereby assuring that only the fluids from theisolated test region can freely enter a liuid recovery chamber providedin the wire line tester of the present invention.

Heretofore, various constructions have been proposed for fluid samplingwire line testers to permit the collecting of fluid samples from a wellbore. However, many of the devices are less than satisfactory inoperation due to the fact that they do not obtain truly representativesamples from that portion of the well bore undergoing testing. Inaddition, most generally, the wire line testers presently utilized relyupon hydrostatic or formation pressure to actuate the various componentsassociated with the collection of fluid samples or data pertainingthereto.

Another problem often encountered with wire line testers proposedheretofore is that of testing a relatively impermeable zone within t-hebore of the well. This is particularly compounded by the fact thatduring the drilling of a well it is necessary to maintain control of thewell and stabilize the walls of the well by maintaining the hydrostaticpressure of the drilling mud at a greater pressure than the formationpressure at any given depth. This inevitably leads to a certain amountof clogging of the interstices of the formation thereby making itdifficult to obtain a truly representative sample of the formation fluidat any given point within the well.

Heretofore, most generally, fluid recovering wire line testers were onlycapable of recovering a relatively small volume of formation fluidthereby resulting ina high proportion of inconclusive tests which areaccordingly time consuming and costly in an industry that is becomingmore and more cost conscious.

This invention proposes to overcome the above mentioned shortcomings offluid recovering wire line testers, known heretofore, by setting forth anovel construction for a wire line tes-ting tool which is suspended fromthe well head by a multistrand insulated electrical cable similar tothat used to run electrical logs, which testing tool utilizes a straddlepacker arrangement to isolate a 3,357,504 Patented Dec. 12, 1967 ICCportion of a well bore, wherein the packers are expanded into grippingengagement with the bore, or casing of the well by an annular pistondriven by expanding gas from the ignition of a combustible gas or thedetonation of an explosive within a firing chamber.

It is another object of this invention to provide a straddle packer wireline tester which is provided with a Huid recovery chamber which may beselectively `altered so as to vary the chamber capacity as required.

A further object of this invention is to provide a straddle packer wireline tester of novel construction which permits each step of the test tobe monitored at the well head thereby assuring that any irregularitiesarising during the course of the test can be readily and quicklydetected.

Still another object of this invention is to provide a straddle packerwire line tester having a plurality of outwardly directed shaped chargesmounted on the exterior thereof, on the portion of the tester betweenthe packers, thereby permitting selective fracturing of the formationbeing tested in order to assure that a truly representative sample offormation fluid is obtained thus substantially eliminating inconclusivetests.

A still further object of this invention is to provide a novel structurefor a straddle packer wire line tester which can be modified at the wellsite to test the bottom few feet of the bore hole by replacing thelowermost packer with a spring steel cage, or inactivating the lowermostof the two packers.

Still another object of this invention is to provide a wire line testerof the type described which is provided with a pressure equalizing tubeso that hydrostatic pressure can be substantially equalized above andbelow the tool during testing thereby overcoming the tendency of thepressures within the well to displace the set tool.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout, and in which:

FIGURE 1 is an elevational view illustrating the tool of the presentinvention as it is lowered into the well bore;

FIGURE 2 is a fragmentary vertical sectionalview of the tool takensubstantially along the plane of the line 2 2 of FIGURE 1;

FIGURE 3 is a fragmentary vertical sectional view of the tool takensubstantially along the plane of the line 3-3 of FIGURE 2 illustratingthe tool with the straddle packer members fully expanded into grippingengagement with the well bore;

FIGURE 4 is a fragmentary vertical sectional view of the tool furtherillustrating the fracturing of a formation by one of a plurality ofshaped charges provided on the exterior of the tool;

FIGURE 5 is a fragmentary vertical sectional view of the tool showingthe flow path of the formation fluid through the intermediate testchamber of the tester and into the formation fluid recovery chamber.

FIGURE 6 is an enlarged horizontal section view taken substantiallyalong the plane of the line 6 6 of FIG- URE 2 illustrating the placementof a plurality of shaped charges and certain details of the packerexpanding means; and

FIGURE 7 is an enlarged horizontal sectional view taken substantiallyalong the plane of the line 7-7 of FIGURE 2.

In an exemplary embodiment of this invention the straddle packer wireline tester comprises a straddle packer arrangement wherein the packersare expanded by a piston driven by a combustible gas in a `firingchamber which is ignited thereby driving the pistons toward the 3packers and expanding them. Simultaneously a plurality of fluid entryports provided in the pistons are shifted to match fluid entry portsprovided in the outside housing of the piston chamber thus opening theinterior of the wire line tester to the annulus between the packers.

A plurality of shaped charges mounted on the outside of the ring chamberare then ignited to selectively perforate the formation being tested tofacilitate uid flow from the formation into the bore hole in the regionbetween the packers. A valve at the base of the formation uid recoverychamber is then actuated to release the trapped hydrostatic pressure inthe test chamber. This valve is then closed and initial shut-in pressureof the formation is recorded and relayed to the well head through thewire line which is provided with a plurality of insulated electricallyconductive cables. A conventional pressure bomb or pressure measuringdevice may be positioned in the test chamber to be used to make a chartof pressures encountered during the test relative to elapsed time toprovide a check on the pressure sensing transducer utilized to relayflow and shut-in-pressures to the well head. After the initialshut-in-pressure has stabilized an electromagnetically operated valve atthe base of the fluid recovery chamber is actuated from the well head tobring the fluid recovery chamber into communication with the testchamber. Fluid resistivity of the iiuid entering the fluid recoverychamber is measured by a resistivity measuring device and the data isrelayed simultaneously to the well head -where it may be recorded forfuture use.

When a test is concluded, the valve between the recovery and testchambers is closed by command from the well head and the finalshut-in-pressure is sensed and relayed to the well head. The straddlepackers are then released by actuating an exhaust valve which connectsthe firing chamber with a gas expansion chamber within the tool therebyventing the expanded gases from the firing chamber into the exhaustchamber thus permitting the resiliency of the rubber packers to returnthe pistons to their original position thereby permitting the wire linetester to be moved within or Iwithdrawn from the bore hole. The exhaustchamber is preferably tted with a check valve so that as the pressure ofthe exhaust gas within the exhaust chamber overcomes hydrostaticpressure within the well when the tool is withdrawn from the well theexhaust gases will be bled off.

Referring now to the drawings and FIGURE 1 in particular there isillustrated a straddle packer wire line tester indicated generally atwhich is in position in a well bore adjacent to a portion of a formationindicated generally at 12 which is to be tested for productivity or thelike. The wire line tester 10 includes a housing means or mandrelindicated generally at 14 which provides a housing means for a testchamber indicated generally at 16 and a fluid recovery chamber 18. Therecovery chamber 18 is provided with a drain plug 21, seen best inFIGURE l. The upper portion of the mandrel 14 is provided with a cablehead or connector 20 to which is secured a wire line 22 provided with aplurality, and preferably at least six, insulated electrical conductorssimilar to that used to run electrical logs. As will become clearhereinafter a total of at least six electrical channels will benecessary for the proper operation of the various test components withinthe wire line tester tool 10.

The wire line tester 10 is further provided with a straddle packingmeans indicated generally at 24 which comprises an upper packer assembly26 and a lower packer assembly 28. The packer assemblies 26 and 28include respective abutments 3i) and 32 which may be threadably securedto the mandrel 14 or secured by means of welding, for example. A pair ofrespective packer members 34 and 36, which are preferably formed of arelatively rigid yet resilient oil resistant rubber such as neoprenerubber, for example, are slidably received about the outer diameter ofthe mandrel 14.

A pair of slidable abutments 38 and 40 are slidably carried by the outerdiameter of the mandrel 14 and are secured to a pair of sliding pistons44 and 46 which are slidably carried by the outer diameter of themandrels 14. Although not shown, the sliding pistons 44 and 46 arepreferably keyed to the mandrel 14 in a manner which permits slidingmotion of the pistons 44 and 46 relative to the mandrel 14 whilepreventing rotation of the pistons 44 and 46 relative to the mandrel 14for reasons which will become clear. The abutments 38 and 40 are securedto the packers 34 and 36 by suitable means such as by adhesive bonding,for example.

An annular cylinder 50 is secured to the outer diameter of the mandrel14 in spaced apart relation therefrom, as seen best in FIGURE 6.Accordingly, it will be seen that an annular ring chamber 52 is definedbetween the outer diameter of mandrel 14, the inner diameter of thecylinder 50 and the axial surfaces of the ends of the sliding pistons 44and 46.

As seen best in FIGURE 2 the mandrel 14 is provided with a plurality offluid entry ports 54 in the mandrel 14 which are preferably positionedabout the periphery of the mandrel 14 at a point between the cylinder 50and the upper and lower packers 26 and 28. The slidable pistons 44 and46 are also provided with a plurality of fluid entry ports 56 and 58which are positioned in the respective slidable pistons 44 and 46 so asto register with the ports 54 in the mandrel 14 when the pistons 44 and46 are moved into the position shown in FIGURES 3, 4 and 5, in a mannerto be described.

The firing chamber 52 is preferably charged with a combustible gas whichis preferably not susceptible to spontaneous combustion at the hightemperatures and pressures existent in deep wells and is also capable ofa great increase in volume upon combustion. As it will become readilyapparent as the description proceeds the combustible gas in the firingchamber 52 is utilized to urge the sliding pistons 44 and 46 outwardlythereby carrying the respective sliding abutments 38 and 40 therewith toexpand the resilient packers 34 and 36 by virtue of their compressionagainst their respective xed abutments 30 and 32. The movement of whichpistons would corresponding to sliding pistons 44 and 46 and the packers34 and 36 in the position illust-rated in FIGURES 3, 4 and 5, whereinthe packers 34 and 36 grippingly engage the wall of the bore hole.

As seen best in FIGURE i6 the cylinder 50 is maintained in spaced apartrelationship from the test charnber portion 16 yof the mandrel 14 by aplurality of shaped charge receivers 60 which :are threadably receivedas at 62 in suitable threaded apertures in the mandrel 14. The receivers62 are provided with shaped charges 61 which may be detonated from thewell head by suitable electrical connection, not shown. In addition,each shaped charge receiver 60 may further be provided with a spacer 64to assist in maintaining the cylinder 50 in proper spaced apart relationwith regard to the mandrel 14. The firing chamber 52 may be charged withthe combustible gas through a suitable charging port 66 which isthreadably or otherwise secured in a suitable aperture in the cylinder50, which aperture communicates with the firing chamber 52. Although notshown, the charging port 66 is preferably provided with a means toprevent the escape of the charging gas thereby facilitating charging ofthe tiring chamber 52.

An electrically operated squib or igniting device 68, seen best inFIGURES 2 and 6 is positioned in communication with the firing chamber52 to provide a means of igniting the combustible gas contained therein.Although not shown, the electrically operated igniting device 68 isconnected by a suitable electrical conductor to the cable 22 and thence`to the well head. As seen best in FIGURE 2 a gas exhausting meansindicated generally at 70 is provided for the accumulation of theexpanded gas from the firing chamber S2 subsequent to the setting of thepackers 34 and 36 in order to release the packers. The exhausting meansincludes a conduit 72 which communicates with the firing chamber 52 andconnects the firing chamber 52 with a gas exhausting chiamber 74 whichhas a considerably greater volumetric capacity than the firing chamber52 in order to permit exhausting of the combustion products within thetiring chamber 52 when it is desired to release the packers 34 and 36.The llow of gas through the conduit 72 is regulated by a solenoidoperated packer release valve 76 interposed in the conduit 72 betweenthe firing chamber 52 and the exhaust chamber 74. Although not shown, asuitable electn'cal conductor connects the solenoid valve 76 with thecable 22 and thence to the well head. The gas exhaust chamber 74 isfurther provided with a pressure release check valve 78 which coacts ina manner to be described to vent excessive pressure from the exhaustchamber 74 as the wire line tester is withdrawn from the Well boresubsequent to testing.

From the foregoing it will be understood that the fluid entry ports 54,56 and 58 must be partially or wholly in registry to permit the entranceof lluid from the well bore into the test chamber portion 16 of themandrel 14.

As seen best in FIGURE 2 the wire line tester 10 is further providedwith a pressure equalizing tube 80 which permits equalization of thehydrostatic pressures above and below the packers 34 and 36 when thepackers are in the set position as shown in FIGURES 3, 4 and 5. Amanually operated valve -82 is interposed in the pressure equalizingtube 80 to permit blocking of the pressure equalizing tube 80 asdesired. The manually operated hydrostatic pressure blocking valve ispreset before the tool is lowered into the well. The valve 82 is leftopen if both packers 34 and 36 lare to be used. When only the to-ppacker 34 is to be used the valve 82 is closed prior to lowering thewire line tester into the bore hole, and accordingly the valve 82remains closed throughout the test.

The test chamber portion 16 of the mandrel 14 is further provided with apressure sensing transducer means 90 which is preferably positionedadjacent the upper por tion of the chamber 16 in the proximity of abulkhead 92 which divides the test chamber portion 16 from the lluidrecovery portion 18. The bulkhead 92 its threadably connected to boththe test chamber portion 16 and the iluid recovery portion 18, in amanner not illustrated, to facilitate the servicing of the variouscomponents within the two chambers. The pressure sensing transducermeans 90 is electrically connected to the well head in a manner similarto the -connection provided for the various other electrically operatedcomponents of the tool 10. A solenoid operated valve 94 is provided toselectively control the passage of lluid from the test chamber 16 intothe lluid recovery chamber 18. Although not shown, the solenoid operatedvalve 94 is connected by a suitable electrical conductor to the wireline or cable 20 to and thence to the well head. A iluid resistivitysensing transducer means 96 is provided in the upper portion of thesolenoid operated valve 94 to permit measurement of the fluidresistivity as it enters the lluid recovery chamber 18 from the testchamber 16 through the solenoid operated valve 94 as seen best in FIGURE5, wherein the arrows illustrate the llow of iluid from the bore holeinto the test chamber 16 through the laligned vapertures 54, 56 and 58and thence through the solenoid control valve 94 into the iluidlrecovery chamber 18.

As seen best in FIGURE 1 the recovery chamber 18 is preferably providedwith a threaded coupling member 19, or the like, to facilitate theinsertion of intermediate lengths of tubing to vary the length of therecovery chamber 18 to facilitate the recovery of varying amounts oflluid from the packed region between the straddle packers duringtesting.

The straddle packer wire line testing tool may further be provided witha pressure bomb 98 which is preferably positioned adjacent thedownwardly converging bottom wall of the test chamber 16. The pressurebomb 98 is of a standard type as previously described.

Having described the construction and coaction of the various componentsof my wire line tester a typical sequence of steps utilizing thestraddle packer wire line tester tool 10 of the present invention willbe described. FIGURES l through 5 sequentially illustrate theutilization of the tester of the present invention.

Referring specically again to FIGURE l the wire line tester 10 isillustrated as having been lowered into an uncased bore hole with theportion of the tester 10 between the straddle packers 34 and 36 adjacentthat portion of the formation 12 to be tested for productivity, etc. Atthis point the tool 10 is supported from the well head solely by meansof the wire line 22. Although not mentioned previously it will beunderstood that the six or more insulated electrically conductive cablesincorporated in the wire line 22 are connected to suitable controlswitches, recording devices, etc., located at the well head for thesequential operation of the various components of the tool and/orrecordation of information being transmitted back to the well head fromthe various components situated Within the wire line tester 10. In theposition shown in FIGURE l and the corresponding fragmentary sectionalView FIGURE 2, it will be seen` that the misalignment of the fluid entryports 54, 56 and 58 does not permit entry of fluid from the bore holeinto the test chamber portion 16. It will also be noted that the packers34 and 36 are in their unexpanded state due to the retracted position ofthe slidable pistons 44 and 46. Accordingly, fluid is free to flow pastthe packers 34 and 36. However, it will be understood that just prior tointroducing the tool into the well it is necessary to open the valve 82to provide communication between the region of the bore beneath thetester with the region of the bore above the tester when the packers areset to prevent any undue differential in hydrostatic pressures above andbelow the packers. At this stage of the operation of the device thesolenoid operated valve 94 between the test chamber 16 and recoverychamber 14 would be in the closed position. Although the valve 94 isillustrated as being of a rotary type as seen in FIGURE 2, it will beunderstood that any suitable type of solenoid operated valve would besatisfactory.

Referring now to FIGURE 3 it may be seen that the straddle packers 34and 36 have been expanded into sealing and gripping engagement with thewall of the bore hole by virtue of the fact that the igniting device 68has been energized from the well head to initiate combustion andattendant expansion, of the combustible gas contained within the firingchamber 52 thereby forcing the Isliding pistons 44 and 46 outwardlyrelatively to the annular cylinder 50 thus compressing the resilientrubber packers between their respective sliding abutments 38 and 40carried by the pistons 46 and 44, and their respective fixed abutments30 and 32 to effect a radial expansion of the respective packer membersinto gripping engagement with the wall of the bore hole. It will beunderstood of course that during the setting of the packers the solenoidoperated packer release valve 76 will be closed thereby preventing theventing of the combustible gas or the products of combustion into thegas exhaust chamber 74. It will be further noted, that as the slidingpistons 44 and 46 move into the position shown in FIG- URE 3 the iluidentry ports 54, 56 and 58 in the respective members 14, 44 and 46 comeinto either partial or complete registry thereby permitting iluid fromthe annulus between the tool and the wall of the bore to enter the testchamber 16. The valve 94 is then actuated from the well head to releasethe trapped hydrostatic pressure in the test chamber 16. The valve 94 isthen reclosed and the initial shut-in-pressure is sensed by the pressuresensing transducer means which transmits the data to the well head.After the initial shut-in-pressure has stabilized the recovery chambervalve 94 is again opened allowing the accumulation of formation fluid inthe fluid recovery chamber 18. The fiuid resitivity of the formationfiuid entering the fiuid recovery chamber 18 may be sensed by the fluidresistivity transducer 96 which then transmits the information to thewell head.

The shaped charges 61 are detonated, as illustrated in FIGURE 4, tocreate a plurality of fissures in the formation 12 adjacent to theshaped charge holding members 60 to facilitate the flow of fluid fromthe formation 12 into the annulus between the straddle packers. Thesequential operation of the valve 94 to effect sensing of the initialshut-in-pressure is identical to that described above in the discussionof the operation of the tool as shown in FIGURE 3.

Referring now particularly to FIGURE 5, a plurality of arrows illustratethe flow of formation fluid through the aligned apertures 54, 56 and 58into the test chamber 16 and thence through the open tiuid recoverychamber valve 94 into the fluid recovery chamber 18. When the test isconcluded, the Valve 94 at the base of the recovery chamber 18 is closedand final shut-in-pressure is sensed by the pressure sensing transducermeans 90 and relayed to the well head for observation and recordation.The resilient packers 34 and 36 are then released by actuating, oropening the packer release valve 76, by command from the well head, topermit exhausting of the products of combustion from the firing chamber52 into the gas exhaust chamber 74 thereby allowing the resilient packermembers 34 and 36 to assume their original shape and accordingly drivethe sliding pistons 44 and 46 back into the position illustrated inFIGURES 1 and 2.

The straddle packer line tester tool 10 may then be withdrawn from thebore hole by means of the wire line 22. As the tool 10 is withdrawn fromthe bore hole the hydrostatic pressure of the drilling mud or fluidwithin the bore hole will decrease. Accordingly, to prevent excessivepressure buildup within, or rupturing of the exhaust gas chamber 74 thepressure relief check valve 78 bleeds off the exhaust gases in acontrolled manner thereby precluding the presence of dangerouslyexcessive pressure within the chamber 74 when the tool 10 is pulled fromthe bore hole. Upon withdrawal of the tool 10 from the bore hole thetiuid retained in the recovery chamber 18 may be drained by removal ofthe drain plug 21 at the base of the recovery chamber 1-8 formeasurement and analysis.

Although not shown, means may be provided to utilize the tool 10 to testthe bottom of the bore hole by providing a means of securing the slidingpiston 44 relative to the mandrel 14 thereby preventing expansion of thelower packer 36 while permitting the setting of the upper packer 34thereby defining a test region which extends substantially from thelower end of the packer 34 to the bottom of the bore hole. Thesequential operation of such an embodiment would be substantiallyidentical to the operation of the exemplary embodiment described supra.

It may therefore be seen that a novel construction has been provided fora straddle packer wire line tester which may be conveniently and readilyutilized to carry out a number of bore hole tests wherein the testingprocedure and recovery of data therefrom is greatly facilitated by theability to control all the operating components of the device from thewell head without having to rely upon conditions within the well for theoperation f the vital components thereof.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention asclaimed.

What is claimed as new is as follows:

1. In combination a well tool provided with means to be suspended in awell bore by a wire line and controllable from the well head to test aformation for productivity and the like comprising a mandrel, straddlepacker means carried by said mandrel, said mandrel including a testchamber portion and a iiuid recovery chamber portion, iiuid entry meanscoacting with said packer means to introduce formation fluid into saidt-est chamber from the region between said packer means, said testchamber being provided with pressure sensing transducing means operativefrom the well head, valve means mounted in the tool and operative fromthe well head to selectively permit flow of fluid from said test chamberportion into said uid recovery chamber portion and said packer meansincluding a packer setting means, said packer setting means includingopposed annular packer expanding pistons slidably carried by saidmandrel and having their opposed axial surfaces maintained in spacedapart relation, annular cylinder means positioned in overlying sealingrelationship to the opposed ends of said slidable pistons to define anannular axially expansible firing chamber between said mandrel, saidcylinder means, and the opposed ends of said slidable pistons, means forcharging said ring chamber with a combustible charge, and chargeignition means mounted Within the tool and actuatable from the well headto ignite said charge to drive said slidable pistons outwardly to expandsaid packers.

2. The combination of claim 1 wherein said fiuid recovery portion ofsaid mandrel is provided with a joint means whereby the capacity of saidrecovery chamber may be varied by adding intermediate chamber portions.

3. In combination a well tool provided with means to be suspended in awell bore by a wireline and controllable from the well head to treat andtest a formation for productivity and the like comprising a mandrel,straddle packer means carried by said mandrel, shaped charge receivermeans carried by said mandrel and said straddle packer means, shapedcharges carried by said charge receiver means, means operable from thewell head to detonate said shaped charges whereby the formation may beselectively fractured, said mandrel including a test chamber portion anda fluid recovery chamber portion, uid entry means coacting with saidpacker means to introduce formation fiuid into said test chamber, saidtest chamber being provided with pressure sensing transducing meansoperatively connected to the well head, valve means operativelycontrolled from the well head to selectively permit flow of fluid fromsaid test chamber portion into said fiud recovery chamber portion, saidstraddle packer means including a packer setting means, said packersetting means including opposed annular packer expanding pistonsslidably carried by said mandrel and having their opposed axial surfacesmaintained in spaced apart relation, annular cylinder means positionedin overlying sealing relationship to the opposed ends of said slidablepistons to define an annular axially expansible firing chamber betweensaid mandrel, said cylinder means, and the opposed ends of said slidablepistons, means for charging said firing chamber with a combustiblecharge, and charge ignition means mounted within the tool and actuatablefrom the well head to ignite said charge to drive said slidable pistonsoutwardly to expand said packers.

4. The combination of claim 3 wherein said liud recovery portion of saidmandrel is provided with a joint means whereby the capacity of saidrecovery chamber may be varied by adding intermediate chamber portions.

5. In combination a well tool provided with means to be suspended in awell bore by a Wire line and controllable from the well head to test aformation for productivity and the like comprising a housing, a pair ofspaced bore hole packers slidable on said housing, a pair of abutmentssecured to said housing outwardly of each of said packers, packersetting means operatively associated with said housing and positionedbetween said packers to conipress said packers against said fixedabutments to effect radial expansion of said packers into gripping,sealing engagement with the wall of the bore to isolate the regionbetween said set packers, iiuid recovery means adapted to recover tiuidfrom the region isolated, said iiuid recovery means including a rstiiuid entry means provided in said housing intermediate of said spacedpackers, a second iiuid entry means provided in said packer settingmeans, said second fluid entry means adapted to be out of registry withsaid rst tiuid entry means when said packers are in their unsetposition, said second fluid entry means adapted to move into registrywith said first fluid entry means to admit fluid to said housing whensaid packer setting means is actuated to set said packers, and sensingmeans mounted within said housing to obtain and transmit data to thewell head pertaining to conditions Within said region isolated saidpacker setting means including opposed annular packer expanding pistonsslidably carried by said housing and having their opposed axial surfacesmaintained in spaced apart relation, annular cylinder means positionedin overlying sealing relationship to the opposed ends of said slidablepistons to define an annular .axially expansible firing chamber betweensaid housing, said cylinder means, and the opposed ends of said slidablepistons, means for charging said firing chamber with a combustiblecharge, and charge ignition means mounted within the tool and actuatablefrom the well head to ignite said charge to drive said slidable pistonsoutwardly to expand said resilient packers.

6. The combination of claim including tiring chamber combustion gasexhausting means, said exhausting means including an exhaust gasexpansion chamber mounted within said test chamber portion, conduitmeans operatively connecting said firing chamber to said exhaustchamber, valve means interposed in said conduit means to selectivelycontrol the exhausting of said firing chamber, and said valve meansbeing operable from the well head.

7. The combination of claim 6 wherein said exhausting means includes anexhaust chamber pressure condition responsive relief valve means.

8. The combination of claim 5 including means for equalizing thehydrostatic pressure above and below said packers, said equalizing meanscomprising a pressure equalizer tube mounted within said housing, saidtube having a rst and a second end, said first end communieating withthe well bore above said isolated region, said second end communicatingwith said Well bore below said isolated region, and valve meansinterposed in said pressure equalizer tube.

9. In combination a well tool provided with means adapted to beSuspended in a well bore by a wire line and controllable from the wellhead to test a formation for productivity and the like comprising ahousing, a pair of spaced bore hole packers slidable on said housing, apair of abutments secured to said housing outwardly of each of saidpackers, packer setting means operatively associated with said housingand positioned between said packers to compress said packers `againstsaid xed abutments to effect radial expansion of said packers intogripping, sealing engagement with the wall of the bore to isolate theregion between said set packers, uid recovery means adapted to recoveruid from the region isolated, said uid recovery means including a irstfluid entry means provided in said housing intermediate of said spacedpackers, a second fluid entry means provided in said packer settingmeans, said second fluid entry means adapted to be out of registry withsaid iirst fluid entry means when said packers are in their unsetposition, said second fluid entry means adapted to move into registrywith said first iiuid entry means to admit iuid to said housing whensaid packer setting means is -actuated to set said packers, sensingmeans mounted Within said housing to obtain and transmit data to thewell head pertaining to conditions within said region isolated, saidpacker setting means including opposed annular packer expanding pistonsslidably carried by said mandrel and having their opposed axial surfacesmaintained in spaced apart relation, annular cylinder means positionedin overlying sealing relationship to the opposed ends of said slidablepistons to define an annular axially expansible chamber means betweensaid mandrel, said cylinder means and the opposed ends of said slidablepistons, and means mounted within the tool and actuatable from the wellhead to pressurize said expansible chamber means to drive said slidablepistons outwardly to expand said packers.

References Cited UNITED STATES PATENTS 2,218,155 10/1940 Rusler 166-147X 2,441,894 5/1948 Mennecier 166--147 X 2,564,198 8/1951 Elkins 166--66X 2,715,444 8/1955 Fewel 166--191 X 2,741,313 4/1956 Bagnell 166-186 X2,751,011 6/1956 Johnston 166-147 X 2,762,441 9/1956 Newlin 166-186 X2,866,508 12/1958 Church 175-4.52 2,947,361 8/1960 Hyde 166-1003,010,517 11/1961 Lanmon 166-55.1 X 3,012,611 12/1961 Haines 166-186 X3,090,436 5/ 1963 Briggs 166-63 3,209,835 10/1965 Bourne et al 166-66 XCHARLES E. OCONNELL, Primary Examiner.

I. A. CALVERT, Assistant Examiner.

9. IN COMBINATION A WELL TOOL PROVIDED WITH MEANS ADAPTED TO BESUSPENDED IN A WELL BORE BY A WIRE LINE AND CONTROLLABLE FROM THE WELLHEAD TO TEST A FORMATION FOR PRODUCTIVITY AND THE LIKE COMPRISING AHOUSING, A PAIR OF SPACED BORE HOLE PACKERS SLIDABLE ON SAID HOUSING, APAIR OF ABUTMENTS SECURED TO SAID HOUSING OUTWARDLY OF EACH OF SAIDPACKERS, PACKER SETTING MEANS OPERATIVELY ASSOCIATED WITH SAID HOUSINGAND POSITIONED BETWEEN SAID PACKERS TO COMPRESS SAID PACKERS AGAINSTSAID FIXED ABUTMENTS TO EFFECT RADIAL EXPANSION OF SAID PACKERS INTOGRIPPING, SEALING ENGAGEMENT WITH THE WALL OF THE BORE TO ISOLATE THEREGION BETWEEN SAID SET PACKERS, FLUID RECOVERY MEANS ADAPTED TO RECOVERFLUID FROM THE REGION ISOLATED, SAID FLUID RECOVERY MEANS INCLUDING AFIRST FLUID ENTRY MEANS PROVIDED IN SAID HOUSING INTERMEDIATE OF SAIDSPACED PACKERS, A SECOND FLUID ENTRY MEANS PROVIDED IN SAID PACKERSETTING MEANS, SAID SECOND FLUID ENTRY MEANS ADAPTED TO BE OUT OFREGISTRY WITH SAID FIRST FLUID ENTRY MEANS WHEN SAID PACKERS ARE INTHEIR UNSET POSITION, SAID SECOND FLUID ENTRY MEANS ADAPTED TO MOVE INTOREGISTRY WITH SAID FIRST FLUID ENTRY MEANS TO ADMIT FLUID TO SAIDHOUSING WHEN SAID PACKER SETTING MEANS IS ACTUATED TO SET SAID PACKERS,SENSING MEANS MOUNTED WITHIN SAID HOUSING TO OBTAIN AND TRANSMIT DATA TOTHE WELL HEAD PERTAINING TO CONDITIONS WITHIN SAID REGION ISOLATED, SAIDPACKER SETTING MEAN INCLUDING OPPOSED ANNULAR PACKER EXPANDING PISTONSSLIDABLY CARRIED BY SAID MANDREL AND HAVING THEIR OPPOSED AXIAL SURFACESMAINTAINED IN SPACED APART RELATION, ANNULAR CYLINDER MEANS POSITIONEDIN OVERLYING SEALING RELATIONSHIP TO THE OPPOSED ENDS OF SAID SLIDABLEPISTONS TO DEFINE AN ANNULAR AXIALLY EXPANSIBLE CHAMBER MEANS BETWEENSAID MANDREL, SAID CYLINDER MEANS AND THE OPPOSED ENDS OF SAID SLIDABLEPISTONS, AND MEANS MOUNTED WITHIN THE TOOL AND ACTUABLE FROM THE WELLHEAD TO PRESSURIZE SAID EXPANSIBLE CHAMBER MEANS TO DRIVE SAID SLIDABLEPISTONS OUTWARDLY TO EXPAND SAID PACKERS.